The 37-year-old woman was reaching into the back seat of her vehicle when a man came up behind her and tried to rape her, according to Officer Chris Trim.

"It's a crime of opportunity. Her back was to the suspect. That was the crime the gentleman was looking for," Trim said.

The woman fought off the assailant, pushing and punching him until he ran off in a northbound direction through the park, Trim said.

The victim described the attacker as a white or Hispanic man, approximately 30 to 40 years old with short, messy dark hair. He was 5 feet 9 inches tall and weighed 165 pounds. She said he had "5 o'clock shadow" beard growth and wore a black sweatshirt.

Police said park officials have ramped up security by adding more patrols around Elk Grove Regional Park.

But, runner Eleane Mego said she's going to carry her pepper spray from now on.

"It's kind of secluded sometimes," Mego said. "I notice there's a lot of runners going back and forth but it kind of varies."

Anyone with information about the assault was urged to call the Elk Grove Police Department Detective Bureau at (916) 478-8060 or Crime Alert at (916) 443-HELP (4357).

Callers to Crime Alert can remain anonymous and may be eligible for a reward of up to $1,000.00. Tips can also be sent via SMS text message by entering CRIMES (274637) on a cell phone, followed by Tip732 (agency identification number) and the message.